The invention relates to a towed ray rake with independent adjustments for the movement of the cut fodder lying on the ground.
There are known rakes, that can be towed normally by tractors with tires, made of an articulated structure with supporting wheels, with a tow and coupling bar and, on the side, with two groups of ray wheels appropriate for moving hay or other fodder lying on the ground.
During the working phase, the groups of ray wheels are extended to the sides of the towed vehicle, along two lines that converge towards the mid line of the machine at the back.
During the transport phase the two groups of ray wheels are instead rotated above the towed vehicle, in a position that makes it occupy a limited space on the road and with the ray rake teeth raised above the ground.
Normally, in passing from the operational position to the transport position, the raking devices, are rotated upwards, towards the middle and then towards the front part of the towed vehicle where the draw bar and the tractor are located with a single operation.
This movement reduces the overall width of the machine to make it appropriate for road transport, during which it is necessary for it to occupy a minimal space of the road. At the same time it is necessary that the teeth of the rakes should be raised from the ground. In the known embodiments, said movement is effected by means of a single command. This activates one or more jacks which command the simultaneous rotation of the groups of rakes, for each of which the three above stated movements are effected simultaneously, and therefore not independent one from the other.
The execution of said movements, in the various known technical embodiments, is carried out by means of normally complex joints and which anyhow are such as to impede the operator from modifying, to his requirements and independently one from the other, the positions of the rakes with respect to the ground and to the frame or part of the frame that supports them.
In fact in a known embodiment, created by the inventor of the present invention, the rake comprises a draw bar that is fixed to a frame that is limited at its back by a beam that ends with the wheel hubs, at its front by a beam that ends on two hinges with an axis converging towards the back of the cart.
Said hinges are connected to two rotating arms, an extension of the front beam of the cart, on which the supports of the two groups of rakes are mounted.
Two jacks join points placed towards the center of the front beam with two wings emerging from the rotating arms, in a way that the activation of the said jacks determines the composite rotation of the two groups of ray rakes.
In another production embodiment, the object of the U.S. Pat. No. 4,977,734 dated Dec. 18, 1990, the machine is constituted of a draw bar and a frame connected by hinges.
On the front beam of the frame we have the wheel hubs, while the back beam is joined by an arm to a jack supported by the draw bar.
The activation of the jack causes the rotation of the frame along the axis where the wheels and hinges connecting the draw bar and frame are placed, as well as the rotation of the supports that sustain the ray rake groups by means of a joint which unites them to a beam that is fixed to the draw bar.
Therefore, by activating the command jack we have the simultaneous upward rotation of the supports of the groups of ray rakes, their rotation towards the middle axis of the frame and towards the front part of the frame.
In another production embodiment, the object of the U.S. Pat. No. 4,974,407 dated 25 Jul. 1994 the machine is composed of a draw bar fixed to a frame to which are anchored the wheel hubs.
On said frame are fixed two tubular guides pointing upwards, towards the back and towards the middle axis of the same frame.
The shafts, that support each one a reverse T-shaped structure on which the groups of ray rakes are placed, are housed within the said guides.
Two jacks connect points positioned towards the center of the frame with the rotation shafts, so that the activation of said jacks determines a composite rotation of the ray rake groups each of which is subjected in this way, during its transit from the working position to that of transfer, to an elevation, to a movement towards the median line of the frame and to a movement towards the tractor.
In the prior art ray rakes, by means of often complex articulations, with the problems that this entails, we have therefore composite movements of the ray rake groups. In the said ray rakes the operator cannot intervene to modify the relationships between each of the three movements of each composite movement.
It is therefore impossible to render at least some of said movements independent one from the other, so as to make each group of ray rakes assume different positions from those foreseen in the project.
Therefore said rigidity impedes the operator from intervening on the disposition of the ray rake groups to adapt them to the terrain in the event in which it should not be flat and/or in the event in which the tractor should move on a road that is on a different level from that of the ground on which the hay or other fodder to be moved is distributed.
Furthermore, the prior art machines do not allow a fine adjustment of the height of the groups of ray rakes to modify the distance of their wire shaped teeth from, the ground where the fodder to be moved is laid out.
Said wire-shaped teeth should in fact skim the ground to be moved by it and, at the same time, they should move the cut fodder.
An imperfect adjustment of the distance of said teeth from the ground, in the event in which this should be sandy, will determine the movement of the fodder, but also of the superficial layer of the same ground which is raised and mixed with the same fodder.
On the other hand a raising by rotation of the ray rake discs determines a change in their orientation, and of that of their flexible teeth, therefore of their efficiency rendering this action disadvantageous.
Furthermore, in the prior art ray rakes, the movement on the ground to pass from one work area to another that is non adjacent requires a rotation operation of the ray rake groups above the cart, with a relatively long activation and a successive corresponding operation to bring the ray rake groups back to their work position.
The aim of the present invention is the realization of a towed type ray rake, the structure of which is easy to produce and which presents articulations that are also easy to manufacture which undergo low stress during their activation to make a safe and durable machine.
Another aim is to manufacture a machine which presents the rotation movements and those of the raising from the ground of the ray rake groups, independent one from the other, so as to allow the operator to chose an optimal position of the same ray rake groups each time, for the transfer of the machine on the field, for the transfer on the road, for the movement of the machine on the ground during working phases, with terrain that could be uneven and of any type, that is clay or sand.
The invention that has allowed to reach said results is realized by a machine comprising:
a draw bar and a cross bar, joined together, the latter aimed to sustaining the supporting means of the groups of ray rakes which are revolving on a plane that is nearly perpendicular to the axis of the draw bar;
supporting and regulating means for raising the cross bar from the ground;
actuator means independent one from the other with which the movement of the supports of the ray rake groups and those of the supporting and regulating means for the raising of the cross bar from the ground and therefore of the ray rake groups supported by it are controlled.
A similarly structured machine is particularly advantageous because it is very simple to realize and therefore has contained costs, since it has actuator means, with which the height of the cross bar from the ground is regulated, which are different from the actuator means with which the rotation of the supporting means of the ray rake groups is controlled.
Other advantages will be apparent, particularly to technicians in this field, by reading the detailed description which follows and which is referred to the preferred embodiment reproduced as an example in the enclosed drawings.